576 ORDER CXLII. GRAMINACE.E. 



14. P latifo'lium, (L.) Smooth. Culm nearly erect. Leaves long, 

 broad, ciliate ; sheath naked, except at the orifice ; spikes 2 — 3, alter- 

 nate, pilose at the base. Glumes orbicular, in three series, the inter- 

 mediate pedicellate ; rachis narrow. — Car. 



15. P. ten'ue. Erect, glabrous. Leaves long, narrow; spikes 4 — 5, 

 alternate, spreading, pilose at the base. Glumes orbicular, in three 

 6eries ; rachis flexuous, narrow. — Geo. and northward. 



16. P. arundina'ceum. (Poir.) Smooth. Spikes alternate, elongated ; 

 spikelets in three series. Glumes obtuse, equal. Leaves ensiform ; 

 margins rough. — Car. 



17. P. altis'simum, (Lee.) Smooth, erect, high. Leaves long; sheaths 

 ciliate at the base and at the orifice ; spikes 4 — 5, alternate, erect, pi- 

 lose at the base. Glumes large, orbiculate, in two series; rachis broad. 

 — N. Car. 



18. P. MACROsrER'MUM, (Flue.) (P. Floridanum, Mich.) Stem erect, 

 glabrous. Leaves long, the lower ones hairy and scabrous, the upper 

 ones becoming nearly glabrous ; throat of the sheath villous ; spikes 

 generally 3 ; rachis hairy at the base. Floivers 1 — 2 from each bud. — 

 U. June — Sept. Common. 3 — 4 feet. 



19. P. lentif'erum, (Lam.) (P. pracox, Walt.) Stem erect, gla- 

 brous. Leaves linear-lanceolate, glabrous ; spikes numerous, with the 

 flowers crowded, two from each bud, and one of them sessile ; rachis 

 hairy at the base. Glumes orbicular, glabrous. — If. May — Aug. 

 Damp soils. 1 — 2 feet. 



20. P. mucrona'tum, (Mich.) Culm glabrous, creeping on the land 

 and swimming in the water. Leaves broad, ciliate at the base ; sheaths 

 broad, swollen, ciliate ; spikes numerous, narrow, the lowest verticil 

 late, others scattered, naked at the base. Glumes ovate, small, in two 

 6eries. — Geo. to Miss. P. natans, Leconte. 



21. P. PURPf'RAs'cEXS, (Ell.) Stem decumbent and erect, branching, 

 glabrous. Leaves long, hairy at the base, dark purple ; spikes numer- 

 ous. Flowers crowded, two from each bud ; rachis hairy at the base. — 

 IX- July — Oct. Common. 12 — 18 inches. 



22. P. undula'tum, (Poir.) (P. plicatulum, Mich.) Leaves somewhat 

 keeled; margins scabrous, ciliate at the base; sheaths smooth; spikes 

 numerous ; rachis flat, glabrous ; margins scabrous ; spikelets in 2 — 4 

 series ; inferior glumes pubescent, superior glabrous. — Geo. and Flor. 



Genus X.— PAN'ICUM. L. 



(The ancient Latin name for some of the species.) 



Glumes 2, unequal, the lower one very small ; the lower 

 florets usually abortive or bearing- stamens only. Palece con- 

 cave, equal, beardless. Seed coated with the palea3. Flowers 

 in loose, scattered panicles or spikes. 



§ 1. Spikes digitate. 



1. P. mol'le, (Mich.) {Eriuclthxt mollis, Kunth.) Stem erect, pubes- 

 cent toward the summit and all the joints. Leaves glabrous, with the 

 throat of the sheath ciliate. Flowers in spikes or racemes. Glumes 2- 



